Electronic plumbing fixture fittings with shaped and limited sensor detection zones

ABSTRACT

The present application discloses electronic plumbing fixture fittings, such as electronic faucets, with a shaped and limited sensor detection zone. Exemplary embodiments include devices with a plurality of overlapping sensors and devices with a single time-of-flight (TOF) sensor capable of detecting the presence or absence of an object whether or not water is flowing out of a discharge outlet in the in a TOF detection zone.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims priority to, and any other benefit of, U.S.Provisional Pat. App. Ser. No. 62/364,342, filed Jul. 20, 2016, and U.S.Provisional Pat. App. Ser. No. 62/523,877, filed Jun. 23, 2017, theentire contents of both of which are hereby incorporated herein byreference in their entireties to the extent that they are not directlyconflicting with the present application. This application is related toU.S. Pat. No. 9,194,110 (“the '110 patent”), which is incorporated byreference in its entirety to the extent that it is not directlyconflicting with the present application.

BACKGROUND

Electronic plumbing fixture fittings are known in the art. The commonlyowned '110 patent discloses exemplary electronic plumbing fixturefittings.

Most automatic touchless faucets with optical sensors operate based onthe principle that the light emitted from a transmitter is reflectedfrom an object and returns to the receiver, and the water is turned onif the received signal exceeds a certain trigger level. Commonly, inorder to have a consistent and repeatable triggering, complex algorithmsfor improved rejection of false positive or false negative are employedbeyond setting a simple trigger level. However, the signal level of thereflected light traveling back to the receiver is affected by thereflectivity of the object—i.e., the color, texture, glossiness,transparency, and size of the object affect how much the light reflectsand returns to the receiver.

SUMMARY

The present application discloses electronic plumbing fixture fittings,such as electronic faucets, with shaped and limited sensor detectionzones.

In some exemplary embodiments, a sensor comprises a time-of-flight (TOF)sensor capable of detecting the presence or absence of an object whetheror not water is flowing out of a discharge outlet in a TOF detectionzone. Surprisingly, it was discovered that an electronic plumbingfixture fitting can use a TOF sensor with the TOF sensor signal aimeddirectly at a stream of water from the discharge outlet and detect theabsence of a hand or other triggering object while water is streamingfrom the discharge outlet to turn off the stream of water.

In an exemplary embodiment, an electronic plumbing fixture fittingcomprises: a faucet body including a discharge outlet, the dischargeoutlet being operable to deliver water through an expected fluid flowvolume; an electronically controlled valve in fluid communication withthe faucet body upstream of the discharge outlet; at least one processorprogrammed to control the electronically controlled valve to selectivelycontrol a flow of fluid from the electronically controlled valve out thedischarge outlet of the faucet body; and a time-of-flight (TOF) sensorin electrical communication with the processor and operably connected tothe faucet body and positioned to transmit a sensing signal toward theexpected fluid flow volume in a sensing signal volume; and wherein atleast one of the at least one processor and the TOF sensor is configuredto create a detection zone inside the sensing signal volume thatoverlaps at least a portion of the expected fluid flow volume; andwherein at least one of the at least one processor and the TOF sensor isconfigured to permit the TOF sensor to detect the presence or absence ofan object in the detection zone whether or not water is flowing out ofthe discharge outlet through the expected fluid flow volume.

BRIEF DESCRIPTION OF DRAWINGS

FIGS. 1A-1B are schematic diagrams of an exemplary electronic plumbingfixture fitting.

FIG. 2 is a schematic diagram of another exemplary electronic plumbingfixture fitting.

FIG. 3 is a schematic electrical/fluid flow schematic diagram of anexemplary electronic plumbing fixture fitting.

FIG. 4 is a schematic diagram of yet another exemplary electronicplumbing fixture fitting.

FIG. 5 is a schematic diagram of still another exemplary electronicplumbing fixture fitting.

FIG. 6 is a schematic representation of exemplary overlapping sensorsignals.

FIGS. 7-12 show exemplary overlapping sensor embodiments with differentoverlapping sensor signal configurations.

FIG. 13 shows another exemplary TOF sensor embodiment.

DETAILED DESCRIPTION

This Detailed Description merely describes exemplary embodiments of theinvention and is not intended to limit the scope of the claims in anyway. Indeed, the invention as claimed is broader than and unlimited bythe preferred embodiments, and the terms used in the claims have theirfull ordinary meaning.

The present application discloses electronic faucets with atime-of-flight (TOF) sensor capable of detecting the presence or absenceof an object whether or not water is flowing out of a discharge outletin the in a TOF detection zone. Although the terms “presence” and“absence” of an object are used throughout, it is to be understood thatthese terms describe different states, that transitions between thesestates are typically used by exemplary systems, and that suchtransitions are inherent in the context of the terms “presence” and“absence” of an object. For example, the “appearance” of an object fromthe perspective of a sensor (a transition from absence to presence) willtypically be used to turn ON the flow of fluid in some exemplarysystems. As another example, the “disappearance” of an object from theperspective of the sensor (a transition from presence to absence) willtypically be used to turn OFF the flow of fluid in those exemplarysystems. Thus, in some exemplary embodiments, a sensor comprises atime-of-flight (TOF) sensor capable of detecting the appearance ordisappearance of an object whether or not water is flowing out of adischarge outlet in a TOF detection zone. Surprisingly, it wasdiscovered that an electronic plumbing fixture fitting can use a TOFsensor with the TOF sensor signal aimed directly at a stream of waterfrom the discharge outlet and detect the disappearance of a hand orother triggering object while water is streaming from the dischargeoutlet to turn off the stream of water. This is surprising at leastbecause the presence of the flowing water while attempting to detect thedisappearance of the object changes the baseline state vis-à-vis thesituation when there is no flowing water while attempting to detect theappearance of the object.

Referring now to FIG. 1A, an exemplary electronic plumbing fixturefitting 10 is shown. Exemplary electronic plumbing fixture fitting 10includes a fixture body 12 including a discharge outlet 14, thedischarge outlet being operable to deliver water 16 through an expectedfluid flow volume 18. In some exemplary embodiments, the expected fluidflow volume 18 comprises a cylinder. In some exemplary embodiments, theexpected fluid flow volume 18 comprises a frustum of a cone. Anelectronically controlled valve 20 (FIG. 3) in fluid communication withthe fixture body 12 upstream of the discharge outlet 14 selectivelycontrols flow of the water 16. At least one processor 22 is programmedto control the electronically controlled valve 20 to selectively controla flow of water 16 from the electronically controlled valve 20 out thedischarge outlet 14 of the fixture body 12. The exemplary electronicplumbing fixture fitting 10 also includes at least one time-of-flight(TOF) sensor 30 in electrical communication with the processor 22 andpositioned inside (or on) the fixture body 12 that transmits a sensingsignal 31 toward the expected fluid flow volume 18 in a sensing signalvolume 32. At least one of the processor 22 and the TOF sensor 30 isconfigured to create a detection zone 34 inside the sensing signalvolume 32 (e.g., a subset of the sensing signal volume 32) that overlapsat least a portion of the expected fluid flow volume 18. In someexemplary embodiments, at least one of the processor 22 and the TOFsensor 30 is configured to permit the TOF sensor 30 to detect thepresence or absence of an object, such as a user's hand, in thedetection zone 34, whether or not water 16 is flowing out of thedischarge outlet 14 through the expected fluid flow volume 18.

Although the processor 22 is shown schematically positioned inside thefixture body 12, in exemplary embodiments, the processor 22 can bepositioned virtually anywhere as long as it can communicate with thesensor 30 and control the valves. “Processor” or “computer” as usedherein includes, but is not limited to, any programmed or programmableelectronic device or coordinated devices that can store, retrieve, andprocess data and may be a processing unit or in a distributed processingconfiguration. Examples of processors include microprocessors,microcontrollers, graphics processing units (GPUs), floating point units(FPUs), reduced instruction set computing (RISC) processors, digitalsignal processors (DSPs), field programmable gate arrays (FPGAs),complex programmable logic devices (CPLDs), etc. Exemplary electronicplumbing fixture fitting 10 has logic for performing the variousfunctions and processes described herein. “Logic,” synonymous with“circuit” as used herein includes, but is not limited to, hardware,firmware, software and/or combinations of each to perform one or morefunctions or actions. For example, based on a desired application orneeds, logic may include a software controlled processor, discrete logicsuch as an application specific integrated circuit (ASIC), programmedlogic device, or other processor. Logic may also be fully embodied assoftware. “Software,” as used herein, includes but is not limited to oneor more computer readable and/or executable instructions that cause aprocessor or other electronic device to perform functions, actions,processes, and/or behave in a desired manner. The instructions may beembodied in various forms such as routines, algorithms, modules orprograms including separate applications or code from dynamically linkedlibraries (DLLs). Software may also be implemented in various forms suchas a stand-alone program, a web-based program, a function call, asubroutine, a servlet, an application, an app, an applet (e.g., a Javaapplet), a plug-in, instructions stored in a memory, part of anoperating system, or other type of executable instructions orinterpreted instructions from which executable instructions are created.It will be appreciated by one of ordinary skill in the art that the formof software is dependent on, for example, requirements of a desiredapplication, the environment it runs on, and/or the desires of adesigner/programmer or the like. In exemplary embodiments, some or allof the software is stored on memory, which includes one or morenon-transitory computer readable media of one or more local or remotedata storage devices (for remote memories, electronic plumbing fixturefitting 10 will include a communications circuit, not shown). As usedherein, “data storage device” means a device for non-transitory storageof code or data, e.g., a device with a non-transitory computer readablemedium. As used herein, “non-transitory computer readable medium” meanany suitable non-transitory computer readable medium for storing code ordata, such as a magnetic medium, e.g., fixed disks in external harddrives, fixed disks in internal hard drives, and flexible disks; anoptical medium, e.g., CD disk, DVD disk, and other media, e.g., RAM,ROM, PROM, EPROM, EEPROM, flash PROM, external flash memory drives, etc.

Referring back to FIG. 1A, in some exemplary embodiments, the processor22 and/or the TOF sensor 30 is configured to exclude from the detectionzone 34 at least a proximal portion of the sensing signal volume 32′between the expected fluid flow volume 18 and the fixture body proximatethe TOF sensor 30, thereby permitting a user to reach under the fixturebody 12 proximate the TOF sensor 30 without causing the processor 22 toopen the electronically controlled valve 20 while it is closed. Thisconfiguration also permits the faucet body 36 proximate the sensingsignal volume to be wiped clean without causing the processor 22 to openthe electronically controlled valve 20 while it is closed. In someexemplary embodiments, the processor 22 and/or the TOF sensor 30 isconfigured to exclude from the detection zone 34 at least a portion ofthe sensing signal volume 32′″ outside the expected fluid flow volume18, i.e., configured to exclude from the detection zone at least adistal portion of the sensing signal volume past the expected fluid flowvolume, thereby permitting a user to walk up to the electronic plumbingfixture fitting without causing the processor to open the electronicallycontrolled valve while it is closed. This configuration also permitsuser activity in front of the TOF sensor in the sensor field 32 awayfrom the expected fluid flow volume 18 without causing the processor 22to open the electronically controlled valve 20 while it is closed.

Referring now to FIG. 1B, in some exemplary embodiments, the processor22 and/or the TOF sensor 30 is configured to create a detection zone 34having a transmission angle α of about 20° to about 25°. Similarly, insome exemplary embodiments, the processor 22 and/or the TOF sensor 30 isconfigured to create a detection zone 34 having a detection depth D ofabout 10 mm to about 80 mm. In some exemplary embodiments, the processor22 and/or the TOF sensor 30 is configured to create a detection zone 34that is a section of a spherical shell, e.g., an intersection of a coneand a spherical shell, with the apex of the cone located at the TOFsensor (the square section in FIG. 2 is for illustrative purposes only).In some exemplary embodiments the TOF sensor 30 is configured to createa sensing signal volume 32 that has a prismatic conical shape with theapex of the cone located at the TOF sensor. The prismatic sides of thecone are defined by a window or aperture and/or lens system set aboutthe emitter and/or detector of the TOF sensor.

An exemplary embodiment of an electronic plumbing fixture fitting ofFIG. 1 is illustrated in FIG. 2 as an electronic faucet 42. In thisexemplary embodiment, the faucet 42 includes a hub 44, a spout 46, awand 50 having a wand hose (not shown; shown in the '110 patent), and ahandle 52 extending from an associated handle hub 53. An upstream end ofthe hub 44 is connected to a mounting surface (such as a counter orsink). An upstream end of the spout 46 is connected to a downstream endof the hub 44. The spout 46 is operable to rotate relative to the hub44. The wand hose (not shown; shown in the '110 patent) extends throughthe hub 44 and the spout 46 and is operable to move within the hub 44and the spout 46. An upstream end of the wand 50 is mounted in adownstream end of the spout 46 and is connected to a downstream end ofthe wand hose. A downstream end of the wand 50 includes a dischargeoutlet 54 through which water 56 is delivered from the faucet 42. Thewand 50 is operable to pull away from the spout 46. The handle 52 isconnected to a side of the hub 44 and is operable to move relative tothe hub 44. Although the faucet 42 has been described as having arotatable spout 46, a pull-out or pull-down wand 50, and a handle 52mounted on the hub 44, one of ordinary skill in the art will appreciatethat, in certain embodiments, the spout 46 could be fixed relative tothe hub 44, the faucet 42 may not include a wand 50, the handle 52 maybe mounted on other locations on the faucet 42 or remote from the faucet42, and/or the handle 52 may be any mechanical or other device that canbe used to operate a mechanical valve. The electronic faucet 42 alsoincludes at least one time-of-flight (TOF) sensor 30 in electricalcommunication with a processor 22 and positioned inside (or on) thefixture body 46 that transmits a sensing signal 31 toward expected fluidflow volume 58 in a sensing signal volume 32. Although the processor 22is shown schematically positioned inside the fixture body 12, inexemplary embodiments, the processor 22 can be positioned virtuallyanywhere as long as it can communicate with the sensor 30 and controlthe valves. In some exemplary embodiments, the processor 22 is locatedin the handle hub 53. In other exemplary embodiments, the processor 22is located proximate the valves below the counter or other surfacesupporting the faucet 42 (e.g., in electronics module 66 shown in U.S.Pat. No. 9,194,110). At least one of the processor 22 and the TOF sensor30 is configured to create a detection zone 34 inside the sensing signalvolume 32 (e.g., a subset of the sensing signal volume 32) that overlapsat least a portion of the expected fluid flow volume 58. In someexemplary embodiments, at least one of the processor 22 and the TOFsensor 30 is configured to permit the TOF sensor 30 to detect thepresence or absence of an object, such as a user's hand, in thedetection zone 34, whether or not water 56 is flowing out of thedischarge outlet 54 through the expected fluid flow volume 58. In someexemplary embodiments, the expected fluid flow volume 58 comprises acylinder. In some exemplary embodiments, the expected fluid flow volume58 comprises a frustum of a cone.

Although the sensing signal volume 32 and the detection zone 34 areshown in the figures as being conical and frustoconical, respectively,other sensor signal configurations are possible, such as (a) a sensingsignal volume that is oval in cross section or (b) a sensing signalvolume that is a flat, rounded rectangle in cross section. In someexemplary embodiments, the processor 22 and/or the TOF sensor 30 and/oran aperture (e.g., a “collimator”) and/or lens system through which thesensing signal passes (and which limits the size thereof) is configuredto create a detection zone 34 having a transmission angle height ofabout 20° to about 25° and a transmission angle width of about 3° toabout 20°. Similarly, in some exemplary embodiments, the processor 22and/or the TOF sensor 30 is configured to create a detection zone 34having a detection depth D (FIG. 1B) of about 10 mm to about 80 mm. Insome exemplary embodiments, the processor 22 and/or the TOF sensor 30and/or an aperture and/or lens system through which the sensing signalpasses (and which limits the size thereof) is configured to create avertically-oriented detection zone 34 having transmission angle width ofabout 3° to about 20° and a transmission angle height of about 35° toabout 90°, e.g., about 40°, or about 60°, or about 90°, or about 35°-45°or about 40°-60° (all starting just below the lower, distal end of thefixture or wand, so they do not trigger the flow of fluid). In someexemplary embodiments, the processor 22 and/or the TOF sensor 30 and/oran aperture and/or lens system through which the sensing signal passes(and which limits the size thereof) is configured to create a detectionzone 34 that is a section of a spherical shell. In some exemplaryembodiments, the detection zone is not oriented vertically, but insteadis oriented at an angle with respect to vertical.

FIG. 3 shows an exemplary electrical and fluid flow representation forthe embodiments of FIGS. 1-2. Other configurations are possible thattake advantage of the TOF configuration herein. In some exemplaryembodiments, the fitting 10, 42 includes a hot water line 70, a coldwater line 72, a mixed water line 74, a mechanical valve 76, and anelectronic valve 20. The hot water line 70 includes a common portion 78,a mechanical valve portion 80, and an electronic valve portion 82. Thecold water line 72 includes a common portion 84, a mechanical valveportion 86, and an electronic valve portion 88. The mixed water line 74includes a mechanical valve portion 90, an electronic valve portion 92,and a common portion 94. These components can be configured and arrangedas discussed in the '110 patent. For example, in exemplary embodiments,an upstream end of the common portion 78 of the hot water line 70connects to a hot water supply 100, and an upstream end of the commonportion 84 of the cold water line 72 connects to a cold water supply102. A downstream end of the common portion 78 of the hot water line 70connects to a hot water tee 104, and a downstream end of the commonportion 84 of the cold water line 72 connects to a cold water tee 106.An upstream end of the mechanical valve portion 80 of the hot water line70 connects to the hot water tee 104, and an upstream end of themechanical valve portion 86 of the cold water line 28 connects to thecold water tee 60. A downstream end of the mechanical valve portion 80of the hot water line 70 connects to the mechanical valve 76, and adownstream end of the mechanical valve portion 4864 of the cold waterline 72 connects to the mechanical valve 76. An upstream end of theelectronic valve portion 88 of the hot water line 70 connects to the hotwater tee 104, and an upstream end of the electronic valve portion 82 ofthe cold water line 72 connects to the cold water tee 106. A downstreamend of the electronic valve portion 88 of the hot water line 70 connectsto the electronic valve 20, and a downstream end of the electronic valveportion 82 of the cold water line 72 connects to the electronic valve20.

A TOF sensor may be used advantageously in sensor operated faucetdesigns in which the sensor is positioned facing downwards into thesink. In this orientation, it is difficult to use prior art infraredsensors because the reflectance of the sink surface varies depending onwhether the sink is wet or dry. Consequently, calibrating a prior artinfrared sensor to avoid a high incidence of false positive and falsenegative detection events under both wet and dry conditions is extremelydifficult. In contrast, activation of the TOF sensor is insensitive toreflectance and the range of activation distances for a TOF sensor canbe set to exclude reflections from the surface of the sink. Referringnow to FIG. 4, another exemplary embodiment 110 is shown. In thisexemplary embodiment 110, a TOF sensor 130 is positioned in theunderside of pipe 46 at the top, and TOF sensor signal 132 aimed downinto a sink 134 partially filled with water 136 to detect the depth ofthe water in the sink 134 (or tub), i.e., detect the distance from theTOF sensor 130 to a surface 138 of the water 136 so that a correspondingprocessor can calculate the depth of the water 136 in the sink usingcalibration data obtained beforehand and shut off the flow of water(e.g., using valve 20, FIG. 3), if needed. In some exemplaryembodiments, calibration is done by a user filling a sink or tub as fullas the user would want it to be filled for a normal task and then usinga user interface to indicate to the processor 22 to remember thisdesired normal depth by e.g., saving data from the TOF sensor 30corresponding to that depth. In exemplary embodiments, the userinterface comprises the user interacting with the TOF sensor 30 (orother sensors) using specific patterns or gestures that are detected bythe TOF sensor 30 (or other sensors) that are translated by theprocessor 22 to enter a program mode and store a depth corresponding tonormal usage of the sink or tub. In addition, or in the alternative, insome exemplary embodiments, calibration is done by a user filling a sinkor tub as full as the user would ever want it to be filled as a maximumdepth and then using a user interface to indicate to the processor 22 toremember this maximum depth by e.g., saving data from the TOF sensor 30corresponding to that maximum depth.

In some exemplary embodiments, the TOF sensor 30 is a STMicroelectronicsmodel VL6180X proximity and ambient light sensing (ALS) module. Althoughnot tested, it is believed that another suitable TOF sensor is theSTMicroelectronics model VL53LOX sensor. In some exemplary embodimentsusing the VL6180X sensor as TOF sensor 30, the VL6180X TOF sensor 30registers are programmed as follows, which permits the VL6180X TOFsensor to detect the presence or absence of an object, such as a user'shand, in the detection zone 34, whether or not water 16, 56 is flowingout of the discharge outlet 14, 54 through the expected fluid flowvolume 18, 58:

  WriteByte (0x0207, 0x01); WriteByte (0x0208, 0x01); WriteByte (0x0096,0x00); WriteByte (0x0097, 0xfd); WriteByte (0x00e3, 0x00); WriteByte(0x00e4, 0x04); WriteByte (0x00e5, 0x02); WriteByte (0x00e6, 0x01);WriteByte (0x00e7, 0x03); WriteByte (0x00f5, 0x02); WriteByte (0x00d9,0x05); WriteByte (0x00db, 0xce); WriteByte (0x00dc, 0x03); WriteByte(0x00dd, 0xf8); WriteByte (0x009f, 0x00); WriteByte (0x00a3, 0x3c);WriteByte (0x00b7, 0x00); WriteByte (0x00bb, 0x3c); WriteByte (0x00b2,0x09); WriteByte (0x00ca, 0x09); WriteByte (0x0198, 0x01); WriteByte(0x01b0, 0x17); WriteByte (0x01ad, 0x00); WriteByte (0x00ff, 0x05);WriteByte (0x0100, 0x05); WriteByte (0x0199, 0x05); WriteByte (0x01a6,0x1b); WriteByte (0x01ac, 0x3e); WriteByte (0x01a7, 0x1f); WriteByte(0x0030, 0x00); WriteByte (0x0011, 0x10); WriteByte (0x010a, 0x30);WriteByte (0x003f, 0x46); WriteByte (0x0031, 0xFF); WriteByte (0x0040,0x63); WriteByte (0x016, 0x00); WriteByte (0x002e, 0x01); WriteByte(0x001b, 0x09); WriteByte (0x003e, 0x31); WriteByte (0x0014, 0x24);

One exemplary implementation of an exemplary system uses a VL6180Xsensor as a TOF sensor 30 mounted in a MOEN brand MOTIONSENSE brandfaucet, model number 7594E. In this exemplary implementation, theexpected fluid flow volume 18, 58 is approximately a cylinder having adiameter of about 12 mm (or a frustum of a cone having a diameter ofabout 12 mm at the top and about 12 mm at the bottom) and the detectionzone 34 has a width of about 50 mm. The expected fluid flow volume 18,58 is approximately 190 mm from the VL6180X TOF sensor 30 at its closestpoint (expected fluid flow volume 18, 58 is approximately parallel withthe longitudinal axis of the hub 44, FIG. 2). With the VL6180X registersprogrammed as discussed above, the VL6180X TOF sensor can detect thepresence or absence of an object, such as a user's hand, in thedetection zone 34, whether or not water 16, 56 is flowing out of thedischarge outlet 14, 54 through the expected fluid flow volume 18, 58.

In the '110 patent, the presence sensor 72 of that patent can beimplemented as a TOF sensor as discussed herein, e.g., a VL6180X TOFsensor 30 with registers programmed as set forth herein (with aprocessor pre-programmed as set forth in the '110 patent, except asclarified herein with respect to the TOF sensor 30). In addition to theteachings herein, or in the alternative, the toggle sensor 70 of thatpatent can be implemented as a TOF sensor as discussed herein, e.g., aVL6180X TOF sensor 30 with registers programmed as set forth herein(with a processor pre-programmed as set forth in the '110 patent, exceptas clarified herein with respect to the TOF sensor 30). Using a TOFsensor discussed above as a presence sensor 72 and/or using a TOF sensoras discussed above as a toggle sensor 70 would have the advantagesdiscussed herein. Additionally, using a TOF sensor as a toggle sensor 70and/or as a presence sensor 72 would have the following additionaladvantages: unlike the intensity-based detection methods, thetime-of-flight detection of the presence is based on the light traveltime measurement and this time measurement is very much independent ofthe reflectivity of the object, i.e., color, surface roughness, andtexture, for instance.

In a different exemplary embodiment, it is further advantageous toposition the TOF sensor of the current invention close to the outlet ofthe faucet such that the axis of the sensing signal volume is close toand parallel or nearly parallel to the central axis of the expectedfluid flow volume. With the TOF sensor positioned thus the surface orsurfaces defining the detection volume that do not intersect theexpected fluid flow volume may be located very near to the surface ofthe fluid flow volume and almost symmetrically about the fluid flowvolume. When the geometries of the sensing signal volume and theexpected fluid flow volume are closely matched, opportunities forinadvertent activation are further minimized. Referring now to FIG. 5,another exemplary embodiment 210 is shown. In this exemplary embodiment210, a TOF sensor 230 is positioned close to the outlet 14, 54 of thefaucet such that the axis of the sensing signal volume is close to andparallel or nearly parallel to the central axis of the expected fluidflow volume 18, 58.

Referring now to FIG. 13, another embodiment with a TOF sensor 30 isshown. In this embodiment, the TOF sensor 30 is positioned in thefixture body 12 or spout 46, proximate the discharge outlet 14, 54through which water 16, 56 is delivered from the faucet 10, 42. In thisexemplary embodiment, wiring (not shown) inside the fixture body 12 orspout 46 connects the TOF sensor 30 with the processor 22. In thisexemplary embodiment, the sensing signal 31 is transmitted tosubstantially overlap the flow of fluid 16, 56, in contrast with some ofthe other embodiments in which the sensor signal 31, A, B crosses theflow of fluid 16, 56.

Referring back to FIGS. 1A, 1B, and 2, and also to FIG. 13, it isapparent that the detection zone 34 (sensing signal volume subset 32″)is both shaped and limited. That is, it is apparent that the detectionzone 34 is shaped like a frustum of a cone because of the nature of theTOF sensor and the detection zone 34 is limited in size and range by thegating of the TOF sensor 30. This is perhaps shown best in FIGS. 1A and13 where there is an active sensing signal volume 32″ forming thedetection zone 34 created by an excluded proximal portion of the sensingsignal volume 32′ between the expected fluid flow volume 18 and thefixture body proximate the TOF sensor 30 and an excluded distal portion32′″ of the sensing signal volume past the expected fluid flow volume.Thus, the previously described embodiments form a shaped and limitedsensor detection zone using a single TOF sensor.

In exemplary embodiments, the shape and limit of a shaped and limitedsensor detection zone are selected to exclude undesirable trigger zones,such as preventing a rotating spout from activating the water when thespout has been rotated to a position outside the sink, for instance. Asanother example, in some faucets with a long handle, the water may beinadvertently turned on when the handle is in the field of view. Inorder to prevent this, in exemplary embodiments, the shape and size(i.e., solid angle) of the light emission cone is shaped such that thetransmitted light will avoid the volume of the space where the handlecan interfere with the automatic activation of the water. As yet anotherexample of the benefit of defined sensing volume in space is in a casewhere the user wants to clean the faucet. When the user wipes the spoutwith a towel, the water is turned on if the towel passed over a singlesensor even though the user's intent was to just wipe the faucet not toturn the water on. This type of accidental activation is eliminated byexcluding such areas by Boolean AND operation the two intersectingfields of view.

Accordingly, in some exemplary embodiments, a shaped and limited sensordetection zone is created using a plurality of sensors in differentlocations with overlapping detection zones. Exemplary embodimentsutilize optical sensor technology with Boolean arithmetic to restrictand define the sensing zone in the 3-dimensional space. As shownconceptually in FIG. 6, in exemplary embodiments, a shaped and limitedsensor zone (cross-hatched in FIG. 6) is formed by intersecting sensorvolumes, e.g., the intersection of a first sensor detection zone A fromsensor A (not shown) and a second sensor detection zone B from sensor B(not shown). Together, sensors A and B form a shaped and limited sensordetection zone. An object detected by sensor A and also detected bysensor B is in the shaped and limited sensor detection zone. Theoverlapping sensor volume defined, therefore, can be said to be A AND B(crosshatched). In some exemplary embodiments, with this coded into thetrigger algorithm of the sensor (and/or a corresponding processor), thewater can be turn on if and only if the object is within the sensingvolume defined by the two intersecting fields of view of the sensors.

FIG. 7 shows an exemplary embodiment in which a transceiver ofelectromagnetic radiation Tx/Rx (e.g., an infrared transceiver) ismounted on the fixture body 12 or spout 46 across from the water 16, 56and a receiver of electromagnetic radiation sensor Rx (e.g., an infrareddetector) is mounted outside the fixture body 12 or spout 46, proximatethe discharge outlet 14, 54 through which water 16, 56 is delivered fromthe faucet 10, 42. In this exemplary embodiment, the sensor Rx detectselectromagnetic radiation emitted by the transceiver Tx/Rx. In thisexemplary configuration, a shaped and limited sensor zone A∩B(cross-hatched in FIG. 7) is formed by intersecting sensor volumes,e.g., the intersection of a first sensor detection zone A from thetransceiver Tx/Rx and a second sensor detection zone B from receiver Rx.Together, the transceiver Tx/Rx and the receiver Rx form a shaped andlimited sensor detection zone. An object detected by transceiver Tx/Rxand also detected by receiver Rx is in the shaped and limited sensordetection zone A∩B. In some exemplary embodiments, with this coded intothe trigger algorithm of the sensor (and/or a corresponding processor),the processor will turn on the water if and only if the triggeringobject is within the sensing volume A∩B defined by the two intersectingfields of view of the sensors. In some exemplary embodiments, thetransceiver Tx/Rx is replaced with a transmitter that transmitselectromagnetic radiation detected by the receiver Rx.

FIG. 8 shows another exemplary embodiment in which a transceiver ofelectromagnetic radiation Tx/Rx (e.g., an infrared transceiver) ismounted on the fixture body 12 or spout 46 across from the water 16, 56(as discussed above) and a receiver of electromagnetic radiation sensorRx (e.g., an infrared detector) is mounted higher up on the fixture body12 or spout 46. In this exemplary embodiment, the sensor Rx detectselectromagnetic radiation emitted by the transceiver Tx/Rx. In thisexemplary configuration, a shaped and limited sensor zone A∩B(cross-hatched in FIG. 8) is formed by intersecting sensor volumes,e.g., the intersection of a first sensor detection zone A from thetransceiver Tx/Rx and a second sensor detection zone B from receiver Rx.Together, the transceiver Tx/Rx and the receiver Rx form a shaped andlimited sensor detection zone. An object detected by transceiver Tx/Rxand also detected by receiver Rx is in the shaped and limited sensordetection zone A∩B. In some exemplary embodiments, with this coded intothe trigger algorithm of the sensor (and/or a corresponding processor),the processor will turn on the water if and only if the triggeringobject is within the sensing volume A∩B defined by the two intersectingfields of view of the sensors. In some exemplary embodiments, thetransceiver Tx/Rx is replaced with a transmitter that transmitselectromagnetic radiation detected by the receiver Rx. In some exemplaryembodiments, a third receiver or transceiver (e.g., C in FIG. 8) is usedto further limit the shape and/or size of the detection zone, e.g.,limiting the detection zone to A∩B∩C.

FIG. 9 shows another exemplary embodiment in which a transmitter ofelectromagnetic radiation Tx (e.g., an infrared LED) and two receiversof electromagnetic radiation sensor Rx1, Rx2 (e.g., infrared detectors)are mounted higher on the fixture body 12 or spout 46 proximate the apexof thereof and aimed upwards (rather than being aimed at the expectedflow of fluid 16, 56 as in other embodiments). In this exemplaryembodiment, the sensors Rx1, Rx2 detect electromagnetic radiationemitted by the transmitter Tx. In this exemplary configuration, a shapedand limited sensor zone A∩B1∩B2 (cross-hatched in FIG. 9) is formed byintersecting sensor volumes, e.g., the intersection of a first sensordetection zone A from the transmitter Tx, a second sensor detection zoneB from receiver Rx1, and a third sensor detection zone B2 from receiverRx2. Together, the transmitter Tx and the receivers Rx 1, Rx2 form ashaped and limited sensor detection zone. An object detected bytransmitter Tx and also detected by receivers Rx 1, Rx2 is inside theshaped and limited sensor detection zone A∩B1∩B2. In some exemplaryembodiments, with this coded into the trigger algorithm of the sensor(and/or a corresponding processor), the processor will turn on the waterif and only if the triggering object is within the sensing volumeA∩B1∩1B2 defined by the three intersecting fields of view of thesensors. In some exemplary embodiments, the transmitter Tx is replacedwith a transceiver Tx/Rx that transmits electromagnetic radiationdetected by the receivers Rx1, Rx2 and also is capable of detecting anobject without input from the receivers Rx 1, Rx2.

FIG. 10 shows another exemplary embodiment that is very similar to FIG.7, except the receiver Rx is mounted in a wand 50. This adds complexityto the system because wiring connecting the receiver Rx to the processor22 (not shown)—or other communication means—must be capable of extendingfrom the fixture body 12 or spout 46 to permit the wand to extendtherefrom.

FIG. 11 shows another exemplary embodiment that is very similar to FIG.9, except the receivers Rx1, Rx2 are mounted in a wand 50. This addscomplexity to the system because wiring connecting the receivers Rx1,Rx2 to the processor 22 (not shown)—or other communication means—must becapable of extending from the fixture body 12 or spout 46 to permit thewand to extend therefrom. Like the embodiment of FIG. 9, an objectdetected by transmitter Tx (or transceiver Tx/Rx) and also detected byreceivers Rx1, Rx2 is inside the shaped and limited sensor detectionzone A∩B1∩B2. In some exemplary embodiments, with this coded into thetrigger algorithm of the sensor (and/or a corresponding processor), theprocessor will turn on the water if and only if the triggering object iswithin the sensing volume A∩B1∩B2 defined by the three intersectingfields of view of the sensors.

FIG. 12 shows another exemplary embodiment that is very similar to FIG.11, sensors are positioned in the fixture body 12 or spout 46, proximatethe discharge outlet 14, 54 through which water 16, 56 is delivered fromthe faucet 10, 42.

In exemplary embodiments, the different overlapping sensors describedherein are located and used to control fluid flow, such as described inthe '110 patent and herein, and/or located and used to control a flow offluid, e.g., by creating an overlapping detection zone that overlaps atleast a portion of an expected fluid flow volume to control the flow offluid.

As can be appreciated from this disclosure, one benefit of theapproaches of FIGS. 7-12 herein is an ability to maintain the use ofinexpensive sensors and electronics but with a simple addition ofanother low-cost sensor a well-defined sensing volume is created in adesired space. In exemplary embodiments, this is optically accomplishedthrough the design of the sensing field of view and the transmittingfield of light source by the use of shaped apertures.

As described herein, when one or more components are described as beingconnected, joined, affixed, coupled, attached, or otherwiseinterconnected, such interconnection may be direct as between thecomponents or may be indirect such as through the use of one or moreintermediary components. Also, as described herein, reference to a“member,” “component,” or “portion” shall not be limited to a singlestructural member, component, or element but can include an assembly ofcomponents, members or elements.

While the present invention has been illustrated by the description ofembodiments thereof, and while the embodiments have been described inconsiderable detail, it is not the intention of the applicants torestrict or in any way limit the scope of the invention to such details.Additional advantages and modifications will readily appear to thoseskilled in the art. For example, detection of presence in the situationwhere the sensor faces downward into the sink such as bathroom faucetand sink where the reflectance of the sink surface varies depending uponthe wetness of the sink surface. In this instance, the range ofactivation is set anywhere between the position of sensor and thesurface of the sink, while excluding any signals from the surface of thesink and farther. As another example, a downward facing TOF sensor ofthe current invention may be used to detect the level of water in thesink. This information may be used, for example, in an application of a“smart” faucet that fills the sink with water to a prescribed levelregardless of the quantity or volume of objects in the sink. As yetanother example, multiple TOF sensors of the current invention havingintersecting or non-intersecting sensing signal volumes may be usedadvantageously to define a detection zone having a shape impossible tocreate with a single TOF sensor. Still further, component geometries,shapes, and dimensions can be modified without changing the overall roleor function of the components. Therefore, the inventive concept, in itsbroader aspects, is not limited to the specific details, therepresentative apparatus, and illustrative examples shown and described.Accordingly, departures may be made from such details without departingfrom the spirit or scope of the applicant's general inventive concept.

What is claimed is:
 1. An electronic plumbing fixture fitting,comprising: a faucet body including a discharge outlet, the dischargeoutlet being operable to deliver water through an expected fluid flowvolume; an electronically controlled valve in fluid communication withthe faucet body upstream of the discharge outlet; at least one processorprogrammed to control the electronically controlled valve to selectivelycontrol a flow of fluid from the electronically controlled valve out thedischarge outlet of the faucet body; and a time-of-flight (TOF) sensorin electrical communication with the processor and operably connected tothe faucet body and positioned to transmit a sensing signal toward theexpected fluid flow volume in a sensing signal volume; and wherein atleast one of the at least one processor and the TOF sensor is configuredto create a detection zone inside the sensing signal volume thatoverlaps at least a portion of the expected fluid flow volume; andwherein at least one of the at least one processor and the TOF sensor isconfigured to permit the TOF sensor to detect the presence or absence ofan object in the detection zone whether or not water is flowing out ofthe discharge outlet through the expected fluid flow volume.
 2. Theelectronic plumbing fixture fitting according to claim 1, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone at least a portion of the sensingsignal volume between the expected fluid flow volume and the faucet bodyproximate the TOF sensor, thereby permitting the faucet body proximatethe sensing signal volume to be wiped clean without causing theprocessor to open the electronically controlled valve while it isclosed.
 3. The electronic plumbing fixture fitting, according to claim1, wherein at least one of the at least one processor and the TOF sensoris configured to exclude from the detection zone at least a distalportion of the sensing signal volume past the expected fluid flowvolume, thereby permitting a user to walk up to the electronic plumbingfixture fitting without causing the processor to open the electronicallycontrolled valve while it is closed.
 4. The electronic plumbing fixturefitting, according to claim 2, wherein at least one of the at least oneprocessor and the TOF sensor is configured to exclude from the detectionzone at least a distal portion of the sensing signal volume past theexpected fluid flow volume, thereby permitting a user to walk up to theelectronic plumbing fixture fitting without causing the processor toopen the electronically controlled valve while it is closed.
 5. Theelectronic plumbing fixture fitting, according to claim 1, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone substantially all of the sensingsignal volume between the expected fluid flow volume and the faucet bodyproximate the TOF sensor, thereby permitting the faucet body proximatethe TOF sensor to be wiped clean without causing the processor to openthe electronically controlled valve while it is closed.
 6. Theelectronic plumbing fixture fitting, according to claim 2, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone substantially all of the sensingsignal volume between the expected fluid flow volume and the faucet bodyproximate the TOF sensor, thereby permitting the faucet body proximatethe TOF sensor to be wiped clean without causing the processor to openthe electronically controlled valve while it is closed.
 7. Theelectronic plumbing fixture fitting, according to claim 3, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone substantially all of the sensingsignal volume between the expected fluid flow volume and the faucet bodyproximate the TOF sensor, thereby permitting the faucet body proximatethe TOF sensor to be wiped clean without causing the processor to openthe electronically controlled valve while it is closed.
 8. Theelectronic plumbing fixture fitting, according to claim 4, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone substantially all of the sensingsignal volume between the expected fluid flow volume and the faucet bodyproximate the TOF sensor, thereby permitting the faucet body proximatethe TOF sensor to be wiped clean without causing the processor to openthe electronically controlled valve while it is closed.
 9. An electronicplumbing fixture fitting, comprising: a faucet body, the faucet bodybeing operable to mount above a mounting surface, the faucet bodyincluding a discharge outlet, the discharge outlet being operable todeliver water through an expected fluid flow volume; an electronicallycontrolled valve in fluid communication with the faucet body upstream ofthe discharge outlet; at least one processor programmed to control theelectronically controlled valve to selectively control a flow of fluidfrom the electronically controlled valve out the discharge outlet of thefaucet body; and a time-of-flight (TOF) sensor operably connected withthe faucet body and positioned to transmit a sensing signal toward theexpected fluid flow volume in a sensing signal volume; and wherein atleast one of the at least one processor and the TOF sensor is configuredto create a detection zone inside the sensing signal volume andoverlapping at least a portion of the expected fluid flow volume;wherein at least one of the at least one processor and the TOF sensor isconfigured to permit the TOF sensor to detect the presence or absence ofan object in the detection zone while no water is flowing out of thedischarge outlet; wherein at least one of the at least one processor andthe TOF sensor is configured to permit the TOF sensor to detect thepresence or absence of an object in the detection zone while deliveredwater is flowing in the expected fluid flow volume in the detectionzone; wherein the TOF sensor is electrically coupled to the at least oneprocessor to communicate to the at least one processor TOF datarepresenting one or more of (a) the presence or absence of an object inthe detection zone, (b) a distance of an object in the detection zone,and (c) a time of travel of a signal indicating an object in thedetection zone; wherein the at least one processor has code causing theat least one processor to selectively open the electronically controlledvalve to cause a flow of fluid from the electronically controlled valveout the discharge outlet in the expected fluid flow volume responsive toat least the TOF data; and wherein the at least one processor has codecausing the at least one processor to selectively close theelectronically controlled valve to stop the flow of fluid from theelectronically controlled valve out the discharge outlet in the expectedfluid flow volume responsive to at least TOF data collected while theflow of fluid is flowing in the expected fluid flow volume in thedetection zone.
 10. The electronic plumbing fixture fitting according toclaim 9, wherein at least one of the at least one processor and the TOFsensor is configured to exclude from the detection zone at least aportion of the sensing signal volume between the expected fluid flowvolume and the faucet body proximate the TOF sensor, thereby permittingthe faucet body proximate the sensing signal volume to be wiped cleanwithout causing the processor to open the electronically controlledvalve while it is closed.
 11. The electronic plumbing fixture fitting,according to claim 9, wherein at least one of the at least one processorand the TOF sensor is configured to exclude from the detection zone atleast a distal portion of the sensing signal volume past the expectedfluid flow volume, thereby permitting a user to walk up to theelectronic plumbing fixture fitting without causing the processor toopen the electronically controlled valve while it is closed.
 12. Theelectronic plumbing fixture fitting, according to claim 10, wherein atleast one of the at least one processor and the TOF sensor is configuredto exclude from the detection zone at least a distal portion of thesensing signal volume past the expected fluid flow volume, therebypermitting a user to walk up to the electronic plumbing fixture fittingwithout causing the processor to open the electronically controlledvalve while it is closed.
 13. The electronic plumbing fixture fitting,according to claim 9, wherein at least one of the at least one processorand the TOF sensor is configured to exclude from the detection zonesubstantially all of the sensing signal volume between the expectedfluid flow volume and the faucet body proximate the TOF sensor, therebypermitting the faucet body proximate the TOF sensor to be wiped cleanwithout causing the processor to open the electronically controlledvalve while it is closed.
 14. The electronic plumbing fixture fitting,according to claim 10, wherein at least one of the at least oneprocessor and the TOF sensor is configured to exclude from the detectionzone substantially all of the sensing signal volume between the expectedfluid flow volume and the faucet body proximate the TOF sensor, therebypermitting the faucet body proximate the TOF sensor to be wiped cleanwithout causing the processor to open the electronically controlledvalve while it is closed.
 15. The electronic plumbing fixture fitting,according to claim 11, wherein at least one of the at least oneprocessor and the TOF sensor is configured to exclude from the detectionzone substantially all of the sensing signal volume between the expectedfluid flow volume and the faucet body proximate the TOF sensor, therebypermitting the faucet body proximate the TOF sensor to be wiped cleanwithout causing the processor to open the electronically controlledvalve while it is closed.
 16. The electronic plumbing fixture fitting,according to claim 12, wherein at least one of the at least oneprocessor and the TOF sensor is configured to exclude from the detectionzone substantially all of the sensing signal volume between the expectedfluid flow volume and the faucet body proximate the TOF sensor, therebypermitting the faucet body proximate the TOF sensor to be wiped cleanwithout causing the processor to open the electronically controlledvalve while it is closed.
 17. The electronic plumbing fixture fitting,according to claim 9: wherein at least one of the at least one processorand the TOF sensor is configured to permit the TOF sensor to detect thepresence or absence of a user's hand in the detection zone while nowater is flowing out of the discharge outlet; wherein at least one ofthe at least one processor and the TOF sensor is configured to permitthe TOF sensor to detect the presence or absence of a user's hand in thedetection zone while delivered water is flowing in the expected fluidflow volume in the detection zone; wherein the TOF sensor iselectrically coupled to the at least one processor to communicate to theat least one processor TOF data representing one or more of (a) thepresence or absence of a user's hand in the detection zone, (b) adistance of a user's hand in the detection zone, and (c) a time oftravel of a signal indicating a user's hand in the detection zone;wherein the at least one processor has code causing the at least oneprocessor to selectively open the electronically controlled valve tocause a flow of fluid from the electronically controlled valve out thedischarge outlet in the expected fluid flow volume responsive to atleast the TOF data indicating the presence of a user's hand in thedetection zone; wherein the at least one processor has code causing theat least one processor to selectively close the electronicallycontrolled valve to stop the flow of fluid from the electronicallycontrolled valve out the discharge outlet in the expected fluid flowvolume responsive to at least TOF data collected while the flow of fluidis flowing in the expected fluid flow volume in the detection zone;wherein at least one of the at least one processor and the TOF sensor isconfigured to exclude from the detection zone at least a portion of thesensing signal volume between the expected fluid flow volume and thefaucet body proximate the TOF sensor, thereby permitting the faucet bodyproximate the sensing signal volume to be wiped clean without causingthe processor to open the electronically controlled valve while it isclosed; and wherein at least one of the at least one processor and theTOF sensor is configured to exclude from the detection zone at least adistal portion of the sensing signal volume past the expected fluid flowvolume, thereby permitting a user to walk up to the electronic plumbingfixture fitting without causing the processor to open the electronicallycontrolled valve while it is closed.
 18. The electronic plumbing fixturefitting, according to claim 16: wherein at least one of the at least oneprocessor and the TOF sensor is configured to permit the TOF sensor todetect the presence or absence of a user's hand in the detection zonewhile no water is flowing out of the discharge outlet; wherein at leastone of the at least one processor and the TOF sensor is configured topermit the TOF sensor to detect the presence or absence of a user's handin the detection zone while delivered water is flowing in the expectedfluid flow volume in the detection zone; wherein the TOF sensor iselectrically coupled to the at least one processor to communicate to theat least one processor TOF data representing one or more of (a) thepresence or absence of a user's hand in the detection zone, (b) adistance of a user's hand in the detection zone, and (c) a time oftravel of a signal indicating a user's hand in the detection zone;wherein the at least one processor has code causing the at least oneprocessor to selectively open the electronically controlled valve tocause a flow of fluid from the electronically controlled valve out thedischarge outlet in the expected fluid flow volume responsive to atleast the TOF data indicating the presence of a user's hand in thedetection zone; wherein the at least one processor has code causing theat least one processor to selectively close the electronicallycontrolled valve to stop the flow of fluid from the electronicallycontrolled valve out the discharge outlet in the expected fluid flowvolume responsive to at least TOF data collected while the flow of fluidis flowing in the expected fluid flow volume in the detection zone;wherein at least one of the at least one processor and the TOF sensor isconfigured to exclude from the detection zone at least a portion of thesensing signal volume between the expected fluid flow volume and thefaucet body proximate the TOF sensor, thereby permitting the faucet bodyproximate the sensing signal volume to be wiped clean without causingthe processor to open the electronically controlled valve while it isclosed; and wherein at least one of the at least one processor and theTOF sensor is configured to exclude from the detection zone at least adistal portion of the sensing signal volume past the expected fluid flowvolume, thereby permitting a user to walk up to the electronic plumbingfixture fitting without causing the processor to open the electronicallycontrolled valve while it is closed.
 19. An electronic plumbing fixturefitting, comprising: a faucet body including a discharge outlet, thedischarge outlet being operable to deliver water through an expectedfluid flow volume; an electronically controlled valve in fluidcommunication with the faucet body upstream of the discharge outlet; atleast one processor programmed to control the electronically controlledvalve to selectively control a flow of fluid from the electronicallycontrolled valve out the discharge outlet of the faucet body; and aplurality of sensors in electrical communication with the processor andoperably connected to the faucet body and positioned to transmit asensing signal toward the expected fluid flow volume in a sensing signalvolume, the plurality of sensors located in different locations andhaving overlapping sensing signal volumes creating a shaped and limitedsensor detection zone that overlaps at least a portion of the expectedfluid flow volume; and wherein at least one of the at least oneprocessor and the plurality of sensors is configured to permit theplurality of sensors to detect the presence or absence of an object inthe detection zone.
 20. The electronic plumbing fixture fitting,according to claim 19, wherein at least one of the at least oneprocessor and the plurality of sensors is configured to permit theplurality of sensors to detect the presence or absence of an object inthe detection zone whether or not water is flowing out of the dischargeoutlet through the expected fluid flow volume.